An unusual case of subclavian-aortic steal syndrome in a pediatric patient with hypoplastic aortic arch with coarctation of the aorta of unusual location is described. Aortography showed hypoplasia of the arcus aorta and severe coarctation proximal to the left subclavian artery associated with an aneurysm formation on the isthmus and descending aorta. The enlargement of the arcus aorta was accomplished by prosthetic patch aortoplasty extending from the ascending to descending aorta via median sternotomy using cardiopulmonary bypass and moderate hypothermia. Postoperatively, the patient is doing well with equalized blood pressure. (Ann Thorac Surg 2000;70:291-2) (C) 2000 by The Society of Thoracic Surgeons.